Many circuits are known in the art for reading ultra sensitive photosensors such as photomultiplier tubes (PMT) or silicon photomultipliers (SiPM). PCT/EP2013/077305 discloses readout circuits for multi-channel photomultiplier common cathode arrays. The readout circuits are connectable to the anode of the photodiodes of the photomultiplier arrays. Using a feedback circuit, the resulting readout circuit is a wideband readout circuit with improved resolution of timing and energy measurements. However, the circuit disclosed in PCT/EP2013/077305 does not provide summation of the signals of the multiple channels.
It is desirable to provide a summation circuit for photomultiplier arrays.